How do add-ons work in football transfers?

Liverpool have agreed a deal worth up to £116m for Germany forward Florian Wirtz – but it is still not entirely clear when the transfer would become a British record.

The basic fee is £100m, which puts it level with Jack Grealish’s transfer from Aston Villa to Manchester City in 2021, Declan Rice’s switch from West Ham to Arsenal in 2023, and Moises Caicedo’s move to Chelsea from Brighton in the same summer.

Yet the latter two of those deals had ‘add-ons’ attached to them – and Wirtz’s transfer includes add-ons of £16m.

These payments are often complex and usually kept secret.

Clubs sometimes say add-ons are ‘easily achievable’ or ‘difficult’.

Easier-to-achieve add-ons can include things like making a basic number of appearances, or scoring a certain amount of goals. Add-ons can also be attached to a team’s success rather than the individual player’s – a club may agree to an add-on requiring an extra payment if they qualify for Europe, for example.

Others can be more ambitious – tied to extreme levels of individual or collective success, like winning the Champions League or the Ballon d’Or.

An example of the difficulty add-ons can present when discussing valuations would be the claims made in the Portuguese media in 2022 that the first additional payment in Darwin Nunez’s £64m-plus-add-ons move from Benfica to Liverpool was triggered by the Uruguayan making just 10 appearances.

In April, Liverpool boss Arne Slot rejected speculation he had not started Nunez in any game since 8 March because it would trigger an additional payment.

Whether Liverpool paid more for Nunez, or club captain Virgil van Dijk – for whom they paid a flat fee of £75m to Southampton in 2017 – cannot be determined without knowing exactly what add-ons were included in the Nunez deal, then figuring out which conditions he has and has not met.

It is common practice these days for transfer fees to have performance-based add-ons. The theory is the selling club gains more if the player goes on to be extremely successful, while the buying club is to some extent protected financially if the transfer doesn’t work out.

In some cases, the total value of add-ons is significant – Real Madrid could end up paying an extra £30m to Borussia Dortmund for Jude Bellingham depending on how successful he is over the course of his career in the Spanish capital, for example.

In others, like the potential £1.7m worth of add-ons Brighton’s £29.78m signing of Greece Under-21 forward Charalampos Kostoulas earlier this week included, are less significant.

These extra amounts certainly add up. Let’s take Manchester United as an example.

In their third-quarter financial results for 2024-25 – announced on 6 June – deep down on page 45 of 47, United confirmed that “under the terms of certain contracts with other football clubs and agents in respect of player transfers, additional amounts, in excess of the amounts included in the cost of registrations, would be payable if certain substantive performance conditions are met”.

United confirmed that as of 31 March 2025, the potential liability was £138.82m. Of that, £112.25m was related to player appearances, team success or new contracts, while £3.19m was around international appearances and £22.03m was related to ‘awards’, with the rest classed as ‘other’.

That entry goes some way to explaining what add-ons are and how they can tot up.

When he signed for United, the club let it be known that one of the add-ons attached to Anthony Martial’s £36m move from Monaco was connected to the France striker winning the Ballon d’Or. This was never realised.

United were also very quick to reject speculation Mason Mount had triggered one of the add-ons included in his transfer from Chelsea by playing for the club in a European final, the Europa League final defeat by Tottenham in May.

The Martial Ballon d’Or one was clearly far more difficult, although United argued at the time that if the forward reached that level of success, they would happily pay the clause on the basis they would have benefited enormously through results on the pitch.

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